The couple used records from their stolen cell phone -- which was in the car -- to track the thief and get the SUV back the next day.

Mike Ryan was running an errand Monday afternoon when a dashboard light indicated his tailgate was ajar. Crest Hill Police Chief Dwayne Wilkerson said Ryan pulled onto a side street to close the hatch and as he "approached the door, he noticed someone near the vehicle out of the corner of his eye and (then) watched someone drive off with the car."

Ryan reported the carjacking to police, and worried that the cell phone he left inside would present additional problems. His wife, however, had other concerns.

"When he told me, the first thing out of my mouth was 'Oh, my God. It won't be around to bring home the new baby,'" Lindsey Ryan said.

She's six-months pregnant with the couple's third child, a boy. They have 8- and 2-year-old daughters.

Lindsey Ryan said her husband suggested they report the stolen phone to police, as well, so they'd be protected from any cell phone bill the thief might rack up.

The pregnant sleuth worked and worked the cell phone list and eventually went with a gut feeling that one of the numbers the teen thief had dialed was the one that would lead her to their car.

Over the next three hours, she called that number 38 times until finally a man answered with an angry "Hello."

She identified herself and said she was looking for the boy who had stolen her car.

"Your number is on my husband's cell records 18 times. I know you know where my Pathfinder is and where the boy who stole it is," she told him. "If you don't tell me, you will be charged as a accomplice in this auto theft."

The 20-year-old man reportedly said, "Miss, I'll call you back in five minutes." Instead, the suspect himself called a few minutes later.

He said, "You're a crazy [expletive] for calling us 38 times [and] keeping us up all night. You can have your car back," Ryan said. He told her where the Pathfinder was parked and she and her husband, along with an investigator with the Tri-County Auto Theft Task Force went to the location.

A warrant was issued for a suspect in the theft, but police are not allowed to publicly identify the juvenile.